1. Field of the Invention
The present invention relates to a hoisting device rope, to an elevator as and to a method of using the hoisting device rope and the elevator.
2. Description of Background Art
Elevator ropes are generally made by braiding from metallic wires or strands and have a substantially round cross-sectional shape. A problem with metallic ropes is, due to the material properties of metal, that they have a high weight and a large thickness in relation to their tensile strength and tensile stiffness. There are also background-art belt-shaped elevator ropes which have a width larger than their thickness. Previously known are, e.g. solutions in which the load-bearing part of a belt-like elevator hoisting rope consists of metal wires coated with a soft material that protects the wires and increases the friction between the belt and the drive sheave. Due to the metal wires, such a solution involves the problem of high weight. On the other hand, a solution described in the specification of EP 1640307 A2 proposes the use of aramid braids as the load-bearing part. A problem with aramid material is mediocre tensile stiffness and tensile strength. Moreover, the behavior of aramid at high temperatures is problematic and constitutes a safety hazard. A further problem with solutions based on a braided construction is that the braiding reduces the stiffness and strength of the rope. In addition, the separate fibers of the braiding can undergo movement relative to each other in connection with bending of the rope, the wear of the fibers being thus increased. Tensile stiffness and thermal stability are also a problem in the solution proposed by the specification of WO 1998/029326, in which the load-bearing part used is an aramid fabric surrounded by polyurethane.